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#include <iostream>
using namespace std;

string sa;
int n,k;
long long res=0;
bool tab[3001][3001];
bool kolor[3001][3001];
bool visit[3001][3001];
int wx[10];
int wy[10];

bool dfs(int x, int y){
    visit[x][y] = 1;
    bool res = 0;
    if(tab[x+1][y])
        res = 1;
    if(tab[x-1][y])
        res = 1;
    if(tab[x][y+1])
        res = 1;
    if(tab[x][y-1])
        res = 1;
    if(kolor[x+1][y] && !visit[x+1][y])
        res = res | dfs(x+1,y);
    if(kolor[x-1][y] && !visit[x-1][y])
        res = res | dfs(x-1,y);
    if(kolor[x][y+1] && !visit[x][y+1])
        res = res | dfs(x,y+1);
    if(kolor[x][y-1] && !visit[x][y-1])
        res = res | dfs(x,y-1);
    return res;

}

void check(){
    bool flag = 1;
    for(int i=1;i<=k;i++){
        if( !visit[wx[i]][wy[i]] ){
            flag = flag & dfs( wx[i],wy[i] );
        }
    }
    for(int i=1;i<=k;i++){
        visit[wx[i]][wy[i]] = 0;
    }
    if(flag){
        //for(int i=1;i<=k;i++){
        //    cout<<wx[i]<<" "<<wy[i]<<endl;
        //}cout<<endl;
        res++;
    }
}
int select(int p, int lx, int ly){
    if( p > k  ){
        check();
        return 0;
    }
    for( int j = ly+1; j <= n; j++ ){
        if( !tab[lx][j] ){
            kolor[lx][j] = 1;
            wx[p] = lx;
            wy[p] = j;
            select(p+1,lx,j);
            kolor[lx][j] = 0;
        }
    }
    for( int i = lx+1; i <= n; i++ ){
        for( int j = 1; j <= n; j++ ){
            if( !tab[i][j] ){
                kolor[i][j] = 1;
                wx[p] = i;
                wy[p] = j;
                select(p+1,i,j);
                kolor[i][j] = 0;
            }
        }
    }
    return 0;
}


int main(){
    ios_base::sync_with_stdio(false);
    cin>>n>>k;
    for(int i=1;i<=n;i++){
        cin>>sa;
        for(int j=1;j<=n;j++){
            if( sa[j-1] == '#' ){
                tab[i][j] = 1;
            }
        }
    }
    select(1,1,0);
    cout<<res % 1000000007 <<endl;
}